package com.util.mybatisgenerator;

import org.mybatis.generator.api.CommentGenerator;
import org.mybatis.generator.api.IntrospectedTable;
import org.mybatis.generator.api.PluginAdapter;
import org.mybatis.generator.api.dom.java.*;
import org.mybatis.generator.api.dom.xml.Attribute;
import org.mybatis.generator.api.dom.xml.TextElement;
import org.mybatis.generator.api.dom.xml.XmlElement;

import java.util.List;

/**
 * 自定义mybatis分页插件
 * @author zhouquan
 * @date 2018-01-31
 */
public class PaginationPlugin extends PluginAdapter{

	@Override    
    public boolean modelExampleClassGenerated(TopLevelClass topLevelClass,IntrospectedTable introspectedTable) {    
        addLimit(topLevelClass, introspectedTable, "page");    
        addLimit(topLevelClass, introspectedTable, "pageSize");    
        addSuperClass(topLevelClass,introspectedTable);  
        return super.modelExampleClassGenerated(topLevelClass,  introspectedTable);    
    }    
  
    @Override    
    public boolean sqlMapSelectByExampleWithoutBLOBsElementGenerated(    
        XmlElement element, IntrospectedTable introspectedTable) {    
        XmlElement isNotNullElement = new XmlElement("if");  
        isNotNullElement.addAttribute(new Attribute("test", "null != page  and pageSize>=0"));  
        isNotNullElement.addElement(new TextElement("limit #{page} , #{pageSize}"));    
        element.addElement(isNotNullElement);    
        return super.sqlMapUpdateByExampleWithoutBLOBsElementGenerated(element,introspectedTable);    
    }    
    
    private void addLimit(TopLevelClass topLevelClass,IntrospectedTable introspectedTable, String name) {    
        CommentGenerator commentGenerator = context.getCommentGenerator();    
        Field field = new Field();    
        field.setVisibility(JavaVisibility.PROTECTED);    
        field.setType(PrimitiveTypeWrapper.getIntegerInstance());    
        field.setName(name);    
        commentGenerator.addFieldComment(field, introspectedTable);    
        topLevelClass.addField(field);    
        char c = name.charAt(0);    
        String camel = Character.toUpperCase(c) + name.substring(1);    
        Method method = new Method();    
        method.setVisibility(JavaVisibility.PUBLIC);    
        method.setName("set" + camel);    
        method.addParameter(new Parameter(PrimitiveTypeWrapper.getIntegerInstance(), name));    
        if(name.equals("page")){   
             method.addBodyLine("this." + name + "= (page-1) * pageSize;");  
        }else{  
            method.addBodyLine("this." + name + "=" + name + ";");    
        }  
        commentGenerator.addGeneralMethodComment(method, introspectedTable);    
        topLevelClass.addMethod(method);    
        method = new Method();    
        method.setVisibility(JavaVisibility.PUBLIC);    
        method.setReturnType(PrimitiveTypeWrapper.getIntegerInstance());    
        method.setName("get" + camel);    
        method.addBodyLine("return " + name + ";");    
        commentGenerator.addGeneralMethodComment(method, introspectedTable);    
        topLevelClass.addMethod(method);    
    }    
      
    //xxxExample类全部继承WebBasicExample  
    public void addSuperClass(TopLevelClass topLevelClass,IntrospectedTable introspectedTable) {  
        topLevelClass.setSuperClass("WebBasicExample");  
        topLevelClass.addImportedType("music.struts2.webBasic.WebBasicExample");    
    }  
    
    @Override
    public boolean validate(List<String> warnings) {    
        return true;    
    }      

}
